Ply turning device for use in the manufacture of pneumatic tyres



H. w. TREvAsKIs 3 173 21 FLY TURNING DEVICE FOR USE 1N THE MANUEACTUEE 8 March 16, 1965 OF PNEUMATIC TYRES 2 Sheets-Sheet l Filed Dec. 9, 1959 March 16, 1965 H. w. TREvAsKls 3,173,821

PLY TURNING DEVICE FOR USE IN THE MANUFACTURE oF PNEUMATIG TYREs 2 Sheets-Sheet 2 Filed Dec. 9, 1959 /fW/NTOR United States Patent Oiilice S'BZi Patented Mar. i6, 1965 3,17'3,S2l PLY TURBHNG DEVECE FR USE IN THE MANU- FCTURE 0F PNEUMA'HC TYRES Henry William Trevaskis, Point ieasanr, Blacirdown, near Leamington Spa, England, assigner, by mesne assignments, to Dunlop Tire and Rubber Corporation, Buialo, N.Y., a corporation New York Filed Dee. 9, 1959, Ser. No. 858,536 2 Claims. (Ci. 156-401) This invention relates to a ply turning device for use in the manufacture ot pneumatic tyres, that is to say a device for use in turning the side portions of tyre carcass plies down the sides of crown formers upon which partially shaped tyre carcasses are built, or for turning the plies up around the bead wires. Normally a tyre building former is rotatable about its central axis which is stationary and plies are turned by a device such as a roller engaging a ply on the former at one point on its periphery and the former is then rotated so that the roller rolls around the whole periphery. The present invention is .applicable to a tyre building apparatus in which the former is stationary during the turning operation. An example of such apparatus is described in my ctn-pending application Serial No. 849,200, tiled October 28, 1959, now U.S. Patent No, 2,997,095.

According -to the present invention a ply turning device comprises a plurality of stiff but iiexible fingers arranged in side-by-side relation and connected each by one end, around a circular mounting so that they define a substantially cylindrical surface coaxially extending from the mounting, mountable coaxially alongside a tyre building former with their tree ends directed towards it, and means for liexing the ingers radially whereby their ends may be adjusted to any desired radius within a predetermined range and caused to engage the side region of a ply on the former and turn it across the side of the former.

One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings in which:

FIGURE l is a fragmentary transverse section of apparatus for turning plies in the manufacture of a pneumatic tyre.

FGURE 2, a similar section to FGURE l, shows the apparatus during a ply turning operation.

FIGURE 3, a fragmentary section on line A A of FIGURES l and 2, drawn to a somewhat larger scale, shows the construction of the ngers.

The ply turning device comprises a substantially cyl-indrical mounting member l as shown in FIGURE l of diameter somewhat less 4than the bead diameter of the tyre which is to be built. A radial flange 2 extends inwardly from the member ll, intermediate its two ends, and carries a cylindrical central bearing sleeve 3 for slidably mounting the apparatus coaxially on the axial shaft of a tyre building former. Around the periphery of the member 1 are positioned a plurality of blade-like spring steel fingers 4 extending substantially longitudinally along its surface and sheathed within an annular bag 5 of tough abrasion lresisting rubber, the bag being of length equal to the ngers. The bag has a mouth 6 at one end of the mounting member 1, and the ends of the fingers near to its mouth are riveted to it. As shown in FIGURE 3, the fingers are disposed in two annular layers in overlapping relation, the adjacent lingers in each layer being spaced apart a distance less than the width of a finger, and the lingers in the top layer are mounted over the spaces of the bottom layer so that the lingers define between them a continuous substantially cylindrical surface within the bag which is a close sliding lit on the mounting member l. Rivets are passed through the overlapping parts of adjacent lingers, and the inner and outer layers of the bag, so as to connect the whole finger assembly together in the form of a sleeve to fit over the mounting member l. An abutment ring 7 is secured to the end of the mounting member, for engagement .by the riveted end of the bag so as to locate it in position. The mounting .member is of length slightly greater than that of the fingers 4 and the bag 5 and at its end opposite t-o that carrying the abutment ring '7 has an annular recess 3 within which is received an inflatable tube 9 in closed annular form. In its deflated condition, as shown in FIGURE 1, the tube lies freely in the recess below the bag and the fingers. On inliation, however, the tube expands radially outwardly forcing the closed end of the bag 5 and the free ends of the ngers 4 out with it and flex-ing the lingers. The diameter of the closed end of the bag can thus be controlled and varied as desired by indating the tube.

in use ot the apparatus for turning a ply down over the shoulders of a crown `former or for turning a ply up over the bead wire, the apparatus is rst coaxially and slidably mounted on the shaft of a tyre building former l0. IFor a ply turning down operation a ply 11 is first mounted on the former and the side regions of the ply are turned down slightly by hand. The tube 9 is inilated until the free ends of the fingers 4 are moved radially outwardly to a radius substantially that of the shoulder of the former. The device is then moved axially towards the former until the fingers engage the ply at the shoulder and lie radially outwardly from it. The device is then Ireciprocated between successive positions on the former shaft causing the free ends of the fingers to be alternately pressed in engagement with and moved just clear of the ply. Each time the device is moved axially away from the former the tube 9 is deiiated slightly so that it next engages the ply at successively decreasing radii, so pressing it progressively and smoothly down the side of the former. The rubber bag 5, sheathing the steel iingers 4, prevents any damage being done to the plies by their ends.

After the ply has been turned down as described or by some other means, the device (if used) is withdrawn and a bead wire l2 and fillers 13 are placed in position if required. The ply is then turned up around the bead Wire a slight degree by hand and the device is again moved axially inwardly towards the former with the tube 9 inated sufficiently for the free ends of the fingers to lie at a radius just greater than that of the bead wire. The free ends of the ngers engage the ply and press it axially inwardly against the tiller strip 13. The device is then recip-rocated as before and the tube 9 is intlated slightly each time the bag 5 and the fingers are clear of the ply, so as to increase the effective radius of the :tree ends of the lingers. The ply is -thus turned over the bead wire and progressively consolidated radially outwardly up the side of the former to produce a smooth turn up as shown in FIGURE 2.

instead of mounting the fingers at the minimum radius of the range or movement of their ends, they may instead be mounted inside a cylindrical member of the maximum radius of this range, and surrounded by an inilatable tube within the cylindrical member, on inliation of which the ends of the fingers will be fiexed inwardly. In any embodiment using such resilient fingers it is necessary only that the lingers should be mounted either at the maximum or minimum radius of the desired range of movement, and be sufiiciently flexible for their ends to reach the minimum or maximum radius, respectively.

One means of axially moving and reciprocating the device is a vacuum operated collapsible bellows as described in my co-pending application Serial No. 853,627,

:it iildrNovember 17, 1959, now U.S. Patent No. 3,058,721.

For this purpose the radial ange 2 of the cylindrical' member 1 is machined at lon its side which will be adjacent the former and has a connection 14 for a vacuum pipe. Thecollapsible'bellowsl is slipped -on the shaft be-v fore the present turning device and when the latter is placed/in position the flat surface-ofthe radial iiange engages the end vofthe bellows. Byapplying Ia vacuum to the vpipe connection inthe flange the bellows can be caused to collapse so as to move the turning device axially towardsr'the former. Aspring ispreferably mounted Within the bellows-for expanding. it when the vacuum is released so yas to move `the turning device away from the former.

Having nowdescribed my invention, what I'claim is:

1; A ply turning device for use in the manufacture of pneumatic tyres comprising a cylindrical mounting ele` ment, a'plurality of Asti lingers each mounted at one end on'said mounting element equidistant from a center of said mounting element and arrangedin two co-axial layers, the iingers of each layer being in equally spaced sidelay-side relationand overlapping-the spaces of the other layer to form a substantially continuous hollow wall of circular cross section extending from said mounting element with the free ends ofthe lingers in a'fplane transverse t-o lthe axis of the wall, saidlingers having suiiicient flexibility and elasticity to iiex'radially about their mounting on said mounting element to change the diameter of the hollow body at the free ends ofthe fingers-and to return to `normal position upon Athe Withdrawal `of said force,-

andrneans contacting said lingers on a circumferential zone spaced from the free ends of said fingers and acting on said fingers in a direction radial to the axis of the wall to iiex said fingers equally in `a radial direction to a radial selected position.

2. A ply turning device for use in the manufacture 4of pneumatic tyres `comprising a-cylindrical mounting element, ap'lurality of stiff ingers each mounted Yat onel end on said mounting element equidistant from a-center of saidmounting element and .arrangedina series toform a substantially continuousrhollow Wallof circular cro-ss section extending from said mounting element with the free ends ofthe` fingers inra-.piane transverse to the axis of the wall, saidfingers havingl suiiicient tiexibility and elasticity to flex radially about their mounting on said mounting'elementto 'change the-diameter of the hollow body-atV the free ends of theiingers and to return to normal position upon the withdrawalof said force, and an iniiatable annularrtube interposed between the lingers adjacent their freeends whereby on inflation of the tube the free ends are urged radially away from the cylindrical member.

References Cited by the Examiner UNITED STATES PATENTS 1,562,754l 1'l/25 Gautier 154-10-4V 1,759,232v 5/30 Gammeter 154'-10.3 1,790,210 1/314 Gammeter' 154-103 2,653,645 9/53` Frazier 154-9 2,743,760 5/56 Beckadolph 154-9y EARL M. BERGERT, Primary Examiner. CARL F. KRAPFT; Examiner. 

1. A PLY TURNING DEVICE FOR USE IN THE MANUFACTURE OF PNEUMATIC TYRES COMPRISING A CYLINDRICAL MOUNTING ELEMENT, A PLURALITY OF STIFF FINGERS EACH MOUNTED AT ONE END ON SAID MOUNTING ELEMENT EQUIDISTANT FROM A CENTER OF SAID MOUNTING ELEMENT AND ARRANGED IN TWO CO-AXIAL LAYERS, THE FINGERS OF EACH LAYER BEING IN EQUALLY SPACED SIDEBY-SIDE RELATION AND OVERLAPPING THE SPACES OF THE OTHER LAYER TO FORM A SUBSTANTIALLY CONTINUOUS HOLLOW WALL OF CIRCULAR CROSS SECTION EXTENDING FROM SAID MOUNTING ELEMENT WITH THE FREE ENDS OF THE FINGERS IN A PLANE TRANSVERSE TO THE AXIS OF THE WALL, SAID FINGERS HAVING SUFFICIENT FLEXIBILITY AND ELASTICITY TO FLEX RADIALLY ABOUT THEIR MOUNTING ON SAID MOUNTING ELEMENT TO CHANGE THE DIAMETER OF THE HOLLOW BODY AT THE FREE ENDS OF THE FINGERS AND TO RE- 